Brake mechanism for hoisting machinery



H. SAW'YER.

BRAKE MECHANISM FOR HOISTING MACHINERY APPLICATION FILED JULY 12. I916.

515x C H'o z new In WW UNITED STATES PA NT IC HARRY SAWYER, OF MUSKEGON, MICHIGAN, ASSIGNOR TO SHAW ELECTRIC. CRANE COMPANY, OF MUSKEGON, MICHIGAN, A CORPORATION OF MICHIGAN.

BRAKE imcnamsm FOB. norsrme MACHINERY.

1,351,792. I Application filed July 12,

To all whom it may concern:

Be it known that I, HARRY SAwYER, a citizen of the United States, residln at Muskegon, in the county of Muskegon, tate of Michigan, have made a certain new and useful Invention in Brake Mechanism for Hoisting Machinery, of which the follow- 7 in is .a specification.

%his invention relates to brake mechanism for hoisting machines. D

The object of the invention is to provide a construction which is simple and eflicient for automatically locking the brake member of a hoisting machine against rotation when the hoisting machine is operating in lowering direction, while permitting free rotation of such member when the hoisting machine is operated in hoisting direction.

A further object of the invention is to provide meansffor accomplishing the looking action above referred to immediately after hoisting ceases and without shock.

Other objects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination, location and relative arrangement of parts, all as will be more fullyv hereinafter set forth, as shown in the accompanying drawing, and finally pointed out in the appended claims.

In the drawing 4 Figure 1 is a View partlyin plan, and partly in longitudinal horizontal section showing a construction embodying the principles of my invention.

Fig. 2 is a detail View showing means to lock a member of the brake.

In the operation of hoisting machines it is the common practice to employ a friction brake mechanism including a brake member designed to rotate freely inthe operation of the hoisting machine in hoisting direction, but frictionally or positively restrained against rotation in reverse direction either by the load or by the hoisting machine when operated in the lowering direction. In the operation of such apparatus it is important to prevent rotation of the brake member inlowering direction at all times and by means which are effective, strong, and durable, and it is among the special purposes of my present invention to provide a simple and eflicient apparatus for accomplishing this result.

In the drawing, 1 designates a shaft which specification of Letters Patent. Patented Sept. 7, 1920.

1916. Serial NO. 108,829.

may constitute or which may besuitably eared to the shaft -of the hoisting drum %not shown). The shaft 1 is operated from. a motor driven shaft 2, (the motor not being shown') through any suitable gearing, such, for example, as indicated by reference numerals 3, 4, 5, and 6. The brake member is shown at 7. This member is mounted loosely upon the shaft 8 as is also the gear 5. of the train of -gearing throu h which shaft'l is driven from shaft 2. 'Ehe brake member 7 is frictionally clamped to gear 5, and is free to rotate with it during the operation of the hoisting'inechanism in hoisting direction but is prevented from rotation in the lowering direction. The frictional coupling of brake member 7 and gear 5, may be accomplished in any convenient or well known manner, as, for instance, through the helicalsurfaces 10 one member of which is carried by or associated with gear 4, and keyed to shaft 8, while the other or cooperating member is carried by or associated with the gear 5,which, as above stated, is loose on shaft 8. A flange member 25 is keyed to shaft 8, while a cooperating flange member 26 is keyed to the hub of gear 5.

The brake member 7 is disposed between these cooperating flange member 25, 26, and friction disks 9 are interposed between the said opposed flanges 25, 26, and the brake member 7, alternate disks 9 being keyed to the brake member 7 and the intermediate disks 9 being keyed to the hubs of the flange members 25, 26. The structure so far described may be of any suitable, convenient or well known arrangement, and in the details thereof form no partof my present invention except as they enter into combina- .tion therewith.v The feature of my present invention is to provide an automatic locking device which will permit the brake member 7 to rotate in one direction but to lock it from rotation in the other direction.

In carrying out the purposes of my invention I associate with the brake member 7, an annular gear structure including respectively left and right helical gear teeth. These may be formed in separate members or otherwise as may be desired. A simple arrangement is shown to which, however, I do not desire to be limited or restricted, wherein the left and right'helical gear teeth are respectively formed on annular rings, 11 1 2 which are bolted or otherwise secured together, and to a peripheral flange 13, of the brake member 7, and which, together form a herring-bone gear. The teeth 0 gear members"11-12," respectively mesh with helical pinions 14, 15, mounted upon ,a stud shaft 16, for free rotation thereon.

Each helical pinion 1415, has mounted thereon, or upon an extension of the hub casing 29. See Fig. 2. The friction members or seats 19, 20, also must be prevented I from being displaced in a direction away from each other underthe pressure of the cone shaped friction members 17, 18, when the latter are forced apart from each other,

and into friction seating relation with rej spect to said cooperating members 19, 20, I under the action of the helical gears 11, 12,

14, 15. This result may be accomplished in any suitable or convenient manner. As exemplifying my invention in a practical embodiment'thereof, I have shown the hub 30, of member 19, bearing against a shoulder 31, on the stud 16, while the hub 32, of

member 20, bears against a bushing 33, which extends through the casing and is held in place by nuts 34, carried by a threaded extension 35 of stud 16. Tis arrangement serves to resist and prevent any separation of the friction cone seats 19, 20, under the influence of the seating pressure exerted thereon by the friction cone members 17 18, while at the same time permitting adjustment of said seats toward and away from each other by properly setting the nuts 34. After the spatial relation of 'the friction seat members 19, 20, has been properly adjusted it may be desirable to adjust the two members 19, 20, together laterally in order to brin them and their associated pinions 14, 15, into proper relation with respect to the gears 11, 12. This may be accomplished in many different ways. A simple arrangement is shown wherein the stud 16; which carries said seats and pinions, is shiftable endwise and is held in shifted position by a set screw 21, tapped through a bearing 36, in the casing in which the end of said stud 16 is received. When the helical pinions 14 15, are shifted or moved endwise toward each other, the friction cones 17 18, are released from their seats 1920, but when said helical pinions are shifted endwise away from each other the cones 17-18, frictionally engage the seats 19 20, thereby constituting an automatic friction lockfor i and allowing) the brake member 7. The action of the helical gear teeth of the gears 11 12, upon the helical teeth of the pinions 14, 15, is to force the pinions 1415, apart from each other and hence to force their associated friction cones 17-18 into enga ement with their respective seats 1920, w en a slight motion of the herring bone gears 1112, in the lowering direction takes lace, and to draw the pinions 14, 15, en wise toward each other, thereby withdrawing the friction cones 17-18, from their seats 19-20, the pinions to run freely, when the herring one gear is rotated inthe hoisting directlon. A proper relation of diameter of the pinions 14-15, angle of the helical teeth thereof, diameter of cone mem ber 1718, angle of cone and coeflicient'of friction of the cone members will insure that any given pressure on the helical teeth of the pinions will cause the associated cone friction members to exert suflicient friction, or more than suflicient, to resist the rotative tendency of the pinion tooth load. In order to allow a reasonable amount of lateral movement to the herring bone gears 11-12, the hubs of the pinions 1415, which are presented toward each other, are extended slightly beyond the faces of the gears, as indicated at 22, so as to insure the space between said pinions. The pinions, it will be seen, are entirely independent of each other and yet they act in unison in the accomplish ment of the locking or holding and in their releasing operation, and this independent mounting of said pinions, together with means for off-setting them slightly endwise from each other, enables slight lateral movement of the herring bone gear without im pairing the proper meshing of their helical teeth with the helical teeth of the pinions.

While I have shown a pair of pinions 14,

15, and a set of cooperating friction cones and seats associated with each pinion, I-

wish it to be understood that my invention is not to be limited in this respect. It will be observed that all of the mechanism including the friction brake, the automatic locking and releasing devices, and gearing intermediate the motor and drum shafts, are inclosed within a housing 23, which, if desired, may be utilized to contain oil orother lubricant for lubricating the various parts each other, a friction cone associated with each pinion and fixed-cone seats to cooperate with said cones.

2. In an automatic brake mechanism, a brake member, and means for operating the same, in combination with right and left helical gears carried by said brake member, a supporting pin, right and left helical pinions mounted upon said pin, and respectively engaged by said helical gears, a friction cone carried by each pinion and acone seat' for cooperation with each cone.

3. In an automatic brake mechanism, a

brake member, means for operating it, and helical gears carried by said brake member, in combination with helical pinions respectively engaged by said gears and displaced endwise with respect to each other, said pinions being slightly offset laterally. from each other at their meeting faces, and friction detion members when the latter are forced apart from each other.

6. In an automatic brake mechanism, a brake member, helical gears carried thereby, helical pinions respectively engaged by said gears to be moved thereby toward and from each other, friction devices associated with said pinions, andmeans for holding said pinions and friction devices in adjusted relation with reference to said helical gears.

7. In an automatic brake mechanism, a brake member, helical gears carried thereby, helical pinions respectively engaged by said gears to be moved thereby toward and from each other, friction devices associated with said pinions, a stud shaft carrying said pinions and friction devices, and means for holding said stud shaft inlongitudinally adjusted position.

8. In an automatic brake mechanism, a brake member, helical gears carried thereby helical pinions respectively engaged by said gears to be moved thereby toward and from each other, friction members respectively connected to said pinions to move therewith, a stud shaft on which said pinions and friction members are loosely mounted, and friction seats rigidly mounted on saidstud shaft, and arranged to receive said friction members when the latter are forced apart from each other.

9. In an automatic brake mechanism, a brake member, helical gears carried thereby, helical pinions respectively engaged by said gears to be moved thereby toward and from each other, friction members respectively connected to said pinions to move therewith, friction seats between which said friction members are disposed and with which they cooperate, means for adjusting the spatial relation of said seats and fixedly retaining them in their adjusted relation.

In testimony whereof I have hereunto set my hand, in the presence of the subscribing wltnesses, on this 20th day of June, A. D.,

. HARRY SAW YER. Witnesses P. J. Kmrnns, T. C. AKIN. 

